From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 8292 invoked by alias); 18 Dec 2007 03:29:38 -0000 Received: (qmail 8282 invoked by uid 22791); 18 Dec 2007 03:29:37 -0000 X-Spam-Status: No, hits=-2.4 required=5.0 tests=AWL,BAYES_00,DK_POLICY_SIGNSOME,SPF_HELO_PASS,SPF_PASS X-Spam-Check-By: sourceware.org Received: from mx1.redhat.com (HELO mx1.redhat.com) (66.187.233.31) by sourceware.org (qpsmtpd/0.31) with ESMTP; Tue, 18 Dec 2007 03:29:32 +0000 Received: from int-mx1.corp.redhat.com (int-mx1.corp.redhat.com [172.16.52.254]) by mx1.redhat.com (8.13.8/8.13.1) with ESMTP id lBI3TOlo031810; Mon, 17 Dec 2007 22:29:24 -0500 Received: from pobox-3.corp.redhat.com (pobox-3.corp.redhat.com [10.11.255.67]) by int-mx1.corp.redhat.com (8.13.1/8.13.1) with ESMTP id lBI3TNVZ006205; Mon, 17 Dec 2007 22:29:23 -0500 Received: from touchme.toronto.redhat.com (IDENT:postfix@touchme.yyz.redhat.com [10.15.16.9]) by pobox-3.corp.redhat.com (8.13.1/8.13.1) with ESMTP id lBI3SxWk003761; Mon, 17 Dec 2007 22:29:23 -0500 Received: from ton.toronto.redhat.com (ton.yyz.redhat.com [10.15.16.15]) by touchme.toronto.redhat.com (Postfix) with ESMTP id B6E258001FF; Mon, 17 Dec 2007 22:28:42 -0500 (EST) Received: from ton.toronto.redhat.com (localhost.localdomain [127.0.0.1]) by ton.toronto.redhat.com (8.13.1/8.13.1) with ESMTP id lBI3SQKR006696; Mon, 17 Dec 2007 22:28:26 -0500 Received: (from fche@localhost) by ton.toronto.redhat.com (8.13.1/8.13.1/Submit) id lBI3SPUc006695; Mon, 17 Dec 2007 22:28:25 -0500 X-Authentication-Warning: ton.toronto.redhat.com: fche set sender to fche@redhat.com using -f To: baiwd Cc: systemtap@sourceware.org Subject: Re: do_mmap fails to work on RHEL5.1GA References: <47671B7F.6060206@cn.fujitsu.com> From: fche@redhat.com (Frank Ch. Eigler) Date: Tue, 18 Dec 2007 03:29:00 -0000 In-Reply-To: <47671B7F.6060206@cn.fujitsu.com> (baiwd@cn.fujitsu.com's message of "Tue, 18 Dec 2007 08:59:43 +0800") Message-ID: User-Agent: Gnus/5.1008 (Gnus v5.10.8) Emacs/21.3 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Scanned-By: MIMEDefang 2.58 on 172.16.52.254 Mailing-List: contact systemtap-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Post: List-Help: , Sender: systemtap-owner@sourceware.org X-SW-Source: 2007-q4/txt/msg00536.txt.bz2 baiwd writes: > When I test with the newest stp on RHEL5.1GA, I found that probe for > do_mmap in memory.stp cannot work correctly. [...] Thanks for testing! > ERROR: probe kernel.function("do_mmap@include/linux/mm.h:1001") > registration error (rc -22) This means that systemtap got addresses it thought plausible, but the kernel refused to actually insert a probe there. I wonder if this is the latent systemtap bug awakened by elfutils 0.131. > By looking through the elf file of linux kernel debug and the source > codes, I think do_mmap and do_mmap2 are inlined functions [...] That by itself is not a problem. We can often find reasonable probing addresses for inlined functions. (Not being able to get at their parameters is a whole different (gcc) problem.) > So I wondered whether memory.stp can be changed as following: > [...] > -probe vm.mmap = kernel.function("do_mmap"), kernel.function("do_mmap2")? { > +probe vm.mmap = kernel.function("do_mmap_pgoff") { This would be a good candidate for the recently added optional/sufficient flag: probe vm.mmap = kernel.function("do_mmap")!, kernel.function("do_mmap_pgoff")!, kernel.function("do_mmap2") { ... } - FChE